For six days between 16-22 October, Kennedy and his advisers discussed what they should do. They informed Harold Macmillan, the British Prime Minister, of the developments in Cuba. Then Kennedy went on national television to alert people to what was happening.

Kennedy was aware that the crucial mid-term elections for Congress were to be held in November. A weak presidential performance in a crisis in October could lead to a disaster for the Democratic Party in the election.

He decided to impose a blockade or quarantine zone around Cuba to bring the Soviet build-up to an end. The United States defined a list of items that were considered offensive weapons, which they would not allowed shipped to Cuba. More than fifty warships were used to implement the blockade line off the Cuban coastline.

United States forces were initially placed on DEFCON 3 alert, which was then increased to DEFCON 2, the highest possible state of alert short of war. All military leave was cancelled. More than 200 ICBMs held in storage in the United States were prepared for launch.

There was a real fear that nuclear war was imminent. In the USA, a cartoon figure, Burt the Turtle, reminded viewers to 'duck and cover'. In schools, children went through an emergency drill in which they took cover under their desks. One Massachusetts schoolgirl wrote a letter to a friend saying 'Can you imagine not seeing another Christmas, Thanksgiving, Easter, birthday, dance, or even Halloween? We're just too young to die'. The sense of danger was also felt around the world.

Most historians agree that it was precisely because the consequences would have been so terrible, that a nuclear war was avoided. Both sides knew that they had nothing to gain from a missile exchange. They both had time to think about the terrible results of making the wrong move.

Based on previous confrontations, it seems that Khrushchev underestimated what Kennedy would so. Now, faced with a firm response, the Soviet Union had little choice but to back down. Kennedy's skill came in offering Khrushchev a way out. When Khrushchev ordered his ships to stop, Kennedy made certain that his government did not sound triumphant. Kennedy's undertaking not to invade Cuba was also critical. The final piece of the bargain was a secret deal in which the Americans agreed to remove their missiles from Turkey.